Secret notes to yourself

I am a month and a half into my study of anniversary and the first thing I've been using my skills for is not in fact writing fast--even if after a month of anniversary I could miraculously do that, but to write secret notes to myself that I don't want others to see.
My notes are predictably on the only thing on a 19 year olds mind, love and war. People I love and people I ...don't. Keeping this kind of information secret from prying eyes is usually a good idea.
If anybody has other applications of secret notes in shorthand, I would be happy to read.

(by michael_lisitsa for everyone)